توسعه مدل CE-QUAL-W2 برای شبیه‌سازی ترکیبات آلی فرار در سامانه رودخانه-مخزن

نوع مقاله: مقاله پژوهشی

نویسندگان

1 دانش‌آموخته کارشناسی ارشد، دانشکده مهندسی عمران، دانشگاه علم و صنعت ایران، تهران

2 استاد، دانشکده مهندسی عمران، دانشگاه علم و صنعت ایران، تهران

3 استادیار، دانشکده محیط زیست، دانشگاه محیط زیست،‌کرج

4 دانشجوی کارشناسی ارشد، دانشکده مهندسی عمران، دانشگاه علم و صنعت ایران، تهران

چکیده

در این تحقیق مدل دو بعدی هیدرودینامیک و انتقال جرم، CE-QUAL-W2، برای شبیه‌سازی ترکیبات آلی فرار در پیکره‎های آبی در حال جریان و ساکن توسعه داده شده و در سامانه رودخانه-مخزن کرخه استفاده شد. برای دستیابی به این هدف، زیربرنامه‎ای در کد برنامه‎نویسی اصلی مدل CE-QUAL-W2 گنجانده شد که فرایند فیزیکی، شیمیایی و بیولوژیکی در سرنوشت ماده آلی فرار را تشریح می‎نماید. به‌منظور ارزیابی درستی عملکرد مدل توسعه داده شده CE-QUAL-W2، معادله پیوستگی جرم ماده آلی فرار در سامانه رودخانه-مخزن کرخه مورد آزمون قرار گرفت و درستی عملکرد زیر برنامه توسعه داده شده در شبیه‎سازی سرنوشت و انتقال این آلودگی تایید شد. در ادامه، پاسخ سامانه رودخانه-مخزن کرخه در اثر ورود ناگهانی آلودگی ترکیبات آلی فرار با شاخص MTBE شبیه‎سازی شد و تأثیر نحوه بهره‎برداری (میزان و محل برداشت آب از مخزن) بر فرایندهای هیدرودینامیکی و انتقال جرم در مخزن مورد بررسی قرار گرفت. بررسی نتایج نشان می‎دهد منظور نمودن اثر تبخیر (فراریت) ماده آلی فرار در مدل توسعه یافته CE-QUAL-W2، منجر به کاهش غلظت آلاینده MTBE در منابع آبی مورد مطالعه نسبت به حالت قبل از توسعه مدل شده است. همچنین تأثیر پارامترهای محیطی مانند سرعت باد، دمای آب و دمای هوا مورد آنالیز حساسیت قرار گرفت. نتایج حاصل از تحلیل حساسیت‌های صورت گرفته نشان می‎دهد که افزایش سرعت باد و دمای آب منجر به افزایش شدت تبخیر ماده آلی فرار و کاهش زمان بازپروری مخزن می‌شود و کاهش دمای هوا باعث کاهش نرخ تبخیر ماده آلی فرار و در نتیجه افزایش غلظت آلاینده می‌شود.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Modifiying the CE-QUAL-W2 Model to Simulate Volatile Organic Compounds in River-Reservoir Systems

نویسندگان [English]

  • Farzaneh Feizi 1
  • abbas afshar 2
  • motahare saadatpour 3
  • Elham Faraji 4
1 MSc Graduate, Department of Civil Engineering, Iran University of Science and Technology, Tehran
2 Prof., Dept. of Civil Engineering, Iran University of Sciences and Technology, Tehran
3 Ass. Prof., Faculty of Environment, University of Environment, Karaj
4 MSc Student, Department of Civil Engineering, Iran University of Sciences and Technology, Tehran
چکیده [English]

In this research, the 2D hydrodynamic and mass transport model, CE-QUAL-W2, is modified to simulate the fate and transport of volatile organic compounds (VOCs) in standing and flowing water bodies. The modifed model is applied to the Karkheh river-reservoir system. For this purpose, a subroutine model is added to the CE-QUAL-W2 source code to simulate the physical, chemical, and biological fate of VOCs in water bodies. In a second step, the VOC mass continuity model is employed to evaluate the performance of the modified CE-QUAL-W2 model. The results confirm the accuracy of the modified CE-QUAL-W2 model. The modified CE-QUAL-W2 model is employed to simulate the Karkheh river-reservoir responses in sudden MTBE spill in Karkheh water body. The effects of reservoir operation (withdraw values and locations) on MTBE fate and transport are investigated. The results show, compared to the old version of the CE-QUAL-W2, the modified version in which VOC evaporation is considered shows a reduction in MTBE concentration in the water body under investigation. Furthermore, the effects of such environmental parameters as wind speed, water temperature, and air temperature on MTBE fate and transport are evaluated. The results show that increasing wind speed and water temperature accelerate the evaporation rate of VOCs and decrease the reservoir cleanup time while reducing air temperature leads to reduced VOC evaporation rates and increased VOC concentration in the water body.

کلیدواژه‌ها [English]

  • Sudden Pollution Spill in Water Body
  • Volatile Organic Compound
  • 2D Hydrodynamic and Water Quality Model
  • CE-QUAL-W2
  • MTBE

1. Saadatpour, M., and Afshar, A. (2013). “Multy objective simulation-optimization approach in pollution spill response management model in reservoirs.” Water Resource Managemnt, 27, 1851-1856.

2. Anderson, M. (1997). Predicted MTBE concentrations in the eastside reservoir, Report to the Metropolitan Water District of Southern California; University of California: Riverside, CA.

3. Mc Card, S.A., and Schladow, S.G. (1998). Health and environmental assessment of MTBE, Report to the Governor and Legislature of the State of California as sponsored by SB 521, University of California and US Toxic Substances Research and Teching Program, Davis, CA, Vol. 1V, Part 5.

4. Stocking, A. J., and Kavanaugh, M. C. (2000). “Modeling volatilization of MTBE from standing surface waters.” J. Environ. Eng., 126 (12), 1131-1136.

5. Heald, P., Schladow, S. G., Reuter, J., and Allen, B. (2005). “Modeling MTBE and BTEX in lakesand reservoirs used for recreational boating.” Environ. Sci. Technol, 39, 1111-1118.

6. Bender, D. A., Asher, W. E., and Zogorski, J. S. (2003). LakeVOC-A deterministic model to estimate volatile organic compound concentrations in reservoirs and lakes, U.S. Geological survey Open-File Report 03-212U, 283 P., USA.

7. Lewis, W.K., and Whitman, W.G. (1924). “Principles of gas adsorption.” Industiral Engineering Chemistry, 16(12), 1215-1220.

8. Shokri, A. (2011). “Multi-objective quantity-quality reservoir operation in sudden pollution.” MSc Thesis, Dept. of Irrigation and Reclamution, University of Tehran, Tehran. Iran. (In Persian)

9. Chung, S. W., and Gu, R. R. (2009). “Prediction of the fate and transport processes of atrazine in a reservoir.” Environmental Management, 44, 46-61.

10. Robbins, G. A., and Gilbert, E. J. (2000). “MTBE: A conservative tracer for estimating biodégradation and hydrodynamic dispersion at underground storage tank sites.” Tracers and Modelling in Hydrogeology Proceedings of the TraM'2000 Conference,  IAHS Pub., Belgium, 262, 235-240.

11. Cole, T.M., and Wells, S.A. (2008). User's guide for CE-QUAL-W2: A two-dimensional, laterally averaged, Washington, DC. hydrodynamic and water quality model, Version 3.5. U.S. Army Corps of Eng, Draft File Report, 20314-1000.

12. Heald, P.C., Schladow, S.G., Reuter, J.E., and Allen, B.C. (2000). “Modeling MTBE and BTEX in lakes and reservoirs used for recreational boating.” Environmental Science and Technology, ES035141Q, Supporting Information Appendix 1

13. Chapra, S.D. (1997). Surface water quality modeling, 1th Ed., Mc Graw-Hill, Inc., New York.

14. Socolofsky, S. A., and Jirka, G. H. (2005). Special topics in mixing and transportprocesses in the environment, 5th Ed., Coastal and Ocean Engineering Division, Texas A&M University, College Station, TX 77843-3136.

15. Heald, P.C., Schladow, S.G., Reuter, J.E., and Allen, B.C. (2000b). “Modeling MTBE and BTEX in lakes and reservoirs used for recreational boating.” Environmental Science and Technology ES035141Q, Supporting Information Appendix 2.

16. Hung H. W. (2005). “Remediation of MTBE contaminated groundwater using adsorbent based permeable reactive barriers.” Doctorial Dissertation in National Cheng Kun University, Tainan, Taiwan.

17. Atkins, P.W. (1986). Physical chemistry, W.H. Freeman and Co., New York.

18. Rathbun, R. E. (2000). “Transport, behavior, and fate of volatile organic compounds in streams.” Critical Reviews in Environmental Science and Technology, 30, 129-295.

19. Robbins, G.A., Wang, S., and Stuart, J. D. (1993). “Using the static headspace method to determine Henry’s Law constants.” Anal.Chem., 65, 3113-3118.

20. Fischer, A., Muller, M., and Klasmeier, J. (2004). “Determination of henry’s law constant for methyl tert-butyl ether (MTBE) at groundwater temperatures.” Chemosphere, 54, 689-694.

21. Staudinger, J., and Roberts, P. V. (2001). “A critical compilation of Henry's law constant temperature dependence relations for organic compound in dilute aqueous solutions.” Chemosphere, 44, 561-576.

22. Kinner, N. E. (2001). Fate, transport and remediation of MTBE, Testimony befor the United States Senate Committee on Environment and Public Works, Salem NH.

23. Alikia, H. (2002). “Rever-reservoir water quality simulation model to analyse total maximum daily loads, Karkheh system as case study.” MSc Thesis, Dept. of Civil Engineering, Iran University of Science and Tech., Tehran, Iran. (In Persian)

24. Mohamadi, H. (2002). “Two dimentional reservoir eutrophication modeling.” MSc Thesis, Dept. of Civil Engineering, Iran University of Science and Tech., Tehran, Iran. (In Persian)